The percentage of adolescents who are overweight or obese in this nation continues to rise dramatically contributing to increased weight-related health problems among youth, including diabetes II, hyperlipidemia, and sleep disorders. The primary aim of this proposal is to determine if an Internet-based intervention designed to reduce binge eating and improve healthy weight regulation will result in reductions in objective binge eating (OBE) and weight loss or maintenance in overweight adolescents who binge eat. Secondary aims are to determine if the intervention will improve dietary behaviors, physical activity, and disordered eating attitudes and behaviors; and, to determine satisfaction with the intervention. 120 high school students from cooperating school districts who are overweight and binge eat will be selected for participation. Overweight will be defined as body mass index (BMI) at or above the 85th percentile. Binge eating will be assessed by diagnostic interview and defined as eating an objectively large amount of food accompanied by loss of control one or more times each week for duration of 3 or more months. Students will be randomized to the intervention or wait-list control and followed for up to 5 months. The primary outcome measures will be change in BMI and frequency of OBE determined by a diagnostic interview. We expect that students in the wait-list control condition will maintain the frequency of OBE and, on average, gain weight from baseline to follow-up. We expect that the intervention group will reduce the frequency of OBE and lose or maintain weight compared to baseline and that these improvements will be maintained at follow-up. The Internet delivery format was chosen for the intervention because adolescents worry about stigmatization associated with weight loss programs, have transportation and cost barriers to treatment, and similar Internet-based programs have proved to be effective with adolescents. The intervention is a 16-week semi-structured program, which includes cognitive-behavioral techniques to reduce binge eating and standard behavioral weight loss strategies that have empirically demonstrated effectiveness and are easily adapted to the Internet format. The proposal focuses on issues directly relevant to NIDDK priorities and the Surgeon General's call to action to prevent and decrease pediatric overweight and obesity, which is a serious public health concern.